Imported Upstream version 1.4upstream/1.4

1 files changed, 314 insertions, 0 deletions

diff --git a/src/cmd/internal/rsc.io/x86/x86asm/objdumpext_test.go b/src/cmd/internal/rsc.io/x86/x86asm/objdumpext_test.go
new file mode 100644
index 000000000..37a5513d3
--- /dev/null
+++ b/src/cmd/internal/rsc.io/x86/x86asm/objdumpext_test.go
@@ -0,0 +1,314 @@
+// Copyright 2014 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x86asm
+
+import (
+	"bytes"
+	"debug/elf"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// Apologies for the proprietary path, but we need objdump 2.24 + some committed patches that will land in 2.25.
+const objdumpPath = "/Users/rsc/bin/objdump2"
+
+func testObjdump32(t *testing.T, generate func(func([]byte))) {
+	testObjdumpArch(t, generate, 32)
+}
+
+func testObjdump64(t *testing.T, generate func(func([]byte))) {
+	testObjdumpArch(t, generate, 64)
+}
+
+func testObjdumpArch(t *testing.T, generate func(func([]byte)), arch int) {
+	if testing.Short() {
+		t.Skip("skipping objdump test in short mode")
+	}
+
+	if _, err := os.Stat(objdumpPath); err != nil {
+		t.Fatal(err)
+	}
+
+	testExtDis(t, "gnu", arch, objdump, generate, allowedMismatchObjdump)
+}
+
+func objdump(ext *ExtDis) error {
+	// File already written with instructions; add ELF header.
+	if ext.Arch == 32 {
+		if err := writeELF32(ext.File, ext.Size); err != nil {
+			return err
+		}
+	} else {
+		if err := writeELF64(ext.File, ext.Size); err != nil {
+			return err
+		}
+	}
+
+	b, err := ext.Run(objdumpPath, "-d", "-z", ext.File.Name())
+	if err != nil {
+		return err
+	}
+
+	var (
+		nmatch  int
+		reading bool
+		next    uint32 = start
+		addr    uint32
+		encbuf  [32]byte
+		enc     []byte
+		text    string
+	)
+	flush := func() {
+		if addr == next {
+			switch text {
+			case "repz":
+				text = "rep"
+			case "repnz":
+				text = "repn"
+			default:
+				text = strings.Replace(text, "repz ", "rep ", -1)
+				text = strings.Replace(text, "repnz ", "repn ", -1)
+			}
+			if m := pcrelw.FindStringSubmatch(text); m != nil {
+				targ, _ := strconv.ParseUint(m[2], 16, 64)
+				text = fmt.Sprintf("%s .%+#x", m[1], int16(uint32(targ)-uint32(uint16(addr))-uint32(len(enc))))
+			}
+			if m := pcrel.FindStringSubmatch(text); m != nil {
+				targ, _ := strconv.ParseUint(m[2], 16, 64)
+				text = fmt.Sprintf("%s .%+#x", m[1], int32(uint32(targ)-addr-uint32(len(enc))))
+			}
+			text = strings.Replace(text, "0x0(", "(", -1)
+			text = strings.Replace(text, "%st(0)", "%st", -1)
+
+			ext.Dec <- ExtInst{addr, encbuf, len(enc), text}
+			encbuf = [32]byte{}
+			enc = nil
+			next += 32
+		}
+	}
+	var textangle = []byte("<.text>:")
+	for {
+		line, err := b.ReadSlice('\n')
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return fmt.Errorf("reading objdump output: %v", err)
+		}
+		if bytes.Contains(line, textangle) {
+			reading = true
+			continue
+		}
+		if !reading {
+			continue
+		}
+		if debug {
+			os.Stdout.Write(line)
+		}
+		if enc1 := parseContinuation(line, encbuf[:len(enc)]); enc1 != nil {
+			enc = enc1
+			continue
+		}
+		flush()
+		nmatch++
+		addr, enc, text = parseLine(line, encbuf[:0])
+		if addr > next {
+			return fmt.Errorf("address out of sync expected <= %#x at %q in:\n%s", next, line, line)
+		}
+	}
+	flush()
+	if next != start+uint32(ext.Size) {
+		return fmt.Errorf("not enough results found [%d %d]", next, start+ext.Size)
+	}
+	if err := ext.Wait(); err != nil {
+		return fmt.Errorf("exec: %v", err)
+	}
+
+	return nil
+}
+
+func parseLine(line []byte, encstart []byte) (addr uint32, enc []byte, text string) {
+	oline := line
+	i := index(line, ":\t")
+	if i < 0 {
+		log.Fatalf("cannot parse disassembly: %q", oline)
+	}
+	x, err := strconv.ParseUint(string(trimSpace(line[:i])), 16, 32)
+	if err != nil {
+		log.Fatalf("cannot parse disassembly: %q", oline)
+	}
+	addr = uint32(x)
+	line = line[i+2:]
+	i = bytes.IndexByte(line, '\t')
+	if i < 0 {
+		log.Fatalf("cannot parse disassembly: %q", oline)
+	}
+	enc, ok := parseHex(line[:i], encstart)
+	if !ok {
+		log.Fatalf("cannot parse disassembly: %q", oline)
+	}
+	line = trimSpace(line[i:])
+	if i := bytes.IndexByte(line, '#'); i >= 0 {
+		line = trimSpace(line[:i])
+	}
+	text = string(fixSpace(line))
+	return
+}
+
+func parseContinuation(line []byte, enc []byte) []byte {
+	i := index(line, ":\t")
+	if i < 0 {
+		return nil
+	}
+	line = line[i+1:]
+	enc, _ = parseHex(line, enc)
+	return enc
+}
+
+// writeELF32 writes an ELF32 header to the file,
+// describing a text segment that starts at start
+// and extends for size bytes.
+func writeELF32(f *os.File, size int) error {
+	f.Seek(0, 0)
+	var hdr elf.Header32
+	var prog elf.Prog32
+	var sect elf.Section32
+	var buf bytes.Buffer
+	binary.Write(&buf, binary.LittleEndian, &hdr)
+	off1 := buf.Len()
+	binary.Write(&buf, binary.LittleEndian, &prog)
+	off2 := buf.Len()
+	binary.Write(&buf, binary.LittleEndian, &sect)
+	off3 := buf.Len()
+	buf.Reset()
+	data := byte(elf.ELFDATA2LSB)
+	hdr = elf.Header32{
+		Ident:     [16]byte{0x7F, 'E', 'L', 'F', 1, data, 1},
+		Type:      2,
+		Machine:   uint16(elf.EM_386),
+		Version:   1,
+		Entry:     start,
+		Phoff:     uint32(off1),
+		Shoff:     uint32(off2),
+		Flags:     0x05000002,
+		Ehsize:    uint16(off1),
+		Phentsize: uint16(off2 - off1),
+		Phnum:     1,
+		Shentsize: uint16(off3 - off2),
+		Shnum:     3,
+		Shstrndx:  2,
+	}
+	binary.Write(&buf, binary.LittleEndian, &hdr)
+	prog = elf.Prog32{
+		Type:   1,
+		Off:    start,
+		Vaddr:  start,
+		Paddr:  start,
+		Filesz: uint32(size),
+		Memsz:  uint32(size),
+		Flags:  5,
+		Align:  start,
+	}
+	binary.Write(&buf, binary.LittleEndian, &prog)
+	binary.Write(&buf, binary.LittleEndian, &sect) // NULL section
+	sect = elf.Section32{
+		Name:      1,
+		Type:      uint32(elf.SHT_PROGBITS),
+		Addr:      start,
+		Off:       start,
+		Size:      uint32(size),
+		Flags:     uint32(elf.SHF_ALLOC | elf.SHF_EXECINSTR),
+		Addralign: 4,
+	}
+	binary.Write(&buf, binary.LittleEndian, &sect) // .text
+	sect = elf.Section32{
+		Name:      uint32(len("\x00.text\x00")),
+		Type:      uint32(elf.SHT_STRTAB),
+		Addr:      0,
+		Off:       uint32(off2 + (off3-off2)*3),
+		Size:      uint32(len("\x00.text\x00.shstrtab\x00")),
+		Addralign: 1,
+	}
+	binary.Write(&buf, binary.LittleEndian, &sect)
+	buf.WriteString("\x00.text\x00.shstrtab\x00")
+	f.Write(buf.Bytes())
+	return nil
+}
+
+// writeELF64 writes an ELF64 header to the file,
+// describing a text segment that starts at start
+// and extends for size bytes.
+func writeELF64(f *os.File, size int) error {
+	f.Seek(0, 0)
+	var hdr elf.Header64
+	var prog elf.Prog64
+	var sect elf.Section64
+	var buf bytes.Buffer
+	binary.Write(&buf, binary.LittleEndian, &hdr)
+	off1 := buf.Len()
+	binary.Write(&buf, binary.LittleEndian, &prog)
+	off2 := buf.Len()
+	binary.Write(&buf, binary.LittleEndian, &sect)
+	off3 := buf.Len()
+	buf.Reset()
+	data := byte(elf.ELFDATA2LSB)
+	hdr = elf.Header64{
+		Ident:     [16]byte{0x7F, 'E', 'L', 'F', 2, data, 1},
+		Type:      2,
+		Machine:   uint16(elf.EM_X86_64),
+		Version:   1,
+		Entry:     start,
+		Phoff:     uint64(off1),
+		Shoff:     uint64(off2),
+		Flags:     0x05000002,
+		Ehsize:    uint16(off1),
+		Phentsize: uint16(off2 - off1),
+		Phnum:     1,
+		Shentsize: uint16(off3 - off2),
+		Shnum:     3,
+		Shstrndx:  2,
+	}
+	binary.Write(&buf, binary.LittleEndian, &hdr)
+	prog = elf.Prog64{
+		Type:   1,
+		Off:    start,
+		Vaddr:  start,
+		Paddr:  start,
+		Filesz: uint64(size),
+		Memsz:  uint64(size),
+		Flags:  5,
+		Align:  start,
+	}
+	binary.Write(&buf, binary.LittleEndian, &prog)
+	binary.Write(&buf, binary.LittleEndian, &sect) // NULL section
+	sect = elf.Section64{
+		Name:      1,
+		Type:      uint32(elf.SHT_PROGBITS),
+		Addr:      start,
+		Off:       start,
+		Size:      uint64(size),
+		Flags:     uint64(elf.SHF_ALLOC | elf.SHF_EXECINSTR),
+		Addralign: 4,
+	}
+	binary.Write(&buf, binary.LittleEndian, &sect) // .text
+	sect = elf.Section64{
+		Name:      uint32(len("\x00.text\x00")),
+		Type:      uint32(elf.SHT_STRTAB),
+		Addr:      0,
+		Off:       uint64(off2 + (off3-off2)*3),
+		Size:      uint64(len("\x00.text\x00.shstrtab\x00")),
+		Addralign: 1,
+	}
+	binary.Write(&buf, binary.LittleEndian, &sect)
+	buf.WriteString("\x00.text\x00.shstrtab\x00")
+	f.Write(buf.Bytes())
+	return nil
+}